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Hard coke blockage of micropores of acidic zeolites generally causes serious catalytic deactivation for many chemical processes. Herein, we report a facile method to synthesize H-mordenite nanosheet assemblies without using any template agent. The assemblies exhibit the high catalytic activity for carbonylation of dimethyl ether because of their large quantity of framework Brønsted acids. The specific morphology of the nanosheet unites improves mass diffusion for both reactants and products. Consequently, the coke precursor species can readily migrate from the micropores to the external surface of the assemblies, inducing the improved catalytic stability through inhibiting hard coke formation in frameworks.

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Herein, we introduce a La 1Àx Sr x CoO 3 perovskite catalyst, substituting for Pt containing LNT catalysts, to remove efficiently NO x from lean-burn engines. The NO x storage/reduction occurred alternatively on the perovskite in successive lean/rich atmospheres, and the NO x conversion reached 71.4% with 100% selectivity to N 2 at 300 C.

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Herein, we report the Pd-doped perovskite La0.7Sr0.3CoO3 as an effective lean NO x trap (LNT) catalyst. This smart perovskite displays excellent NO x reduction activities for lean-burn exhausts (NO x conversion >90%, N2 selectivity >90%) over a wide operating temperature range (275–400 °C), as well as an extremely high sulfur tolerance. Our results evidenced Pd dissolving into or segregating out of perovskite in lean-burn and fuel-rich atmospheres. The segregated metallic Pd from perovskite in fuel-rich atmospheres is crucial for obtaining these promising achievements. These findings provide a new possibility for the application of the Pd-based LNT catalysts.

Refractory high-entropy alloys present attractive mechanical properties, i.e., high yield strength and fracture toughness, making them potential candidates for structural applications. Understandings of atomic and electronic interactions are important to reveal the origins for the formation of high-entropy alloys and their structure−dominated mechanical properties, thus enabling the development of a predictive approach for rapidly designing advanced materials. Here, we report the atomic and electronic basis for the valence−electron-concentration-categorized principles and the observed serration behavior in high-entropy alloys and highentropy metallic glass, including MoNbTaW, MoNbVW, MoTaVW, HfNbTiZr, and Vitreloy-1 MG (Zr 41 Ti 14 Cu 12.5 Ni 10 Be 22.5 ). We find that the yield strengths of high-entropy alloys and high-entropy metallic glass are a power-law function of the electron-work function, which is dominated by local atomic arrangements. Further, a reliance on the bonding-charge density provides a groundbreaking insight into the nature of loosely bonded spots in materials. The presence of strongly bonded clusters and weakly bonded glue atoms imply a serrated deformation of high-entropy alloys, resulting in intermittent avalanches of defects movement.

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